The photo shows the completed class D 600W 160m and 80m amplifier, mains power supply and antenna change over board. The front pannel connectors provide a connection to the transmit o/c output from the drive transciever (FT817ND, background right). All RF connections and made via the back pannel. The white plastic box houses the slow start circuit from a microwave oven and the rewound oven transformer is on the left. All mains wiring (should be) double insulated. Fuses (a) rear pannel mains input fuse 10A (b) slowstart fuse 10A (c) 24v mosfet fuse 30A.
The following GNU radio application adds a waterfall spectrogram to the previous CW filter program. The plot show 4 CW signals in the audio band (lower sideband) at 7023 kHz. The 700Hz signal is filtered and output to the laptop headphones by the CW bandpass filter. The frequency display is shown after the script which is as follows: #!/usr/bin/env python from gnuradio import gr from gnuradio import audio from lpf_bpf_class import Bandpass from gnuradio.qtgui import qtgui from PyQt4 import QtGui import sys, sip class cw_filter(gr.top_block): def __init__(self): gr.top_block.__init__(self) sample_rate = 44100 out_rate = 8000 kaiser = Bandpass() cw_flr = gr.fir_filter_fff(1, kaiser.bpftaps) decimate = int(sample_rate/out_rate) Bandpass.cutoff1 = 3000 pre_decim = Bandpass() dec_flr = gr.fir_filter_fff(1, pre_decim.lpftaps) dec = gr.keep_one_in_n(gr.sizeof_float, decima
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